Ionizational Energy Flashcards
What are the Factors Affecting Ionization Energy
- Size of the Atom
- Shielding Effect
- Nuclear Charge
- Electronic Configuration : Atoms having half filled or completely filled orbitals are comparatively more stable and hence higher IE.
What is Ionization energy?
The minimum amount of energy required to remove the outermost electron from an isolated gaseous atom in its ground state to produce a cation is IE.
The lesser Ionization Energy , the better the ability to form cations.
On moving from left to right in the period what happens to IE?
On moving from left to right in the period, the ionization increases.
P.S. Helium has the highest IE in the periodic table.
On moving from top to bottom in a group what happens to IE?
Increases
What are the irregularities in general trend of IE?
Due to extra stability of exactly half filled and completely filled electronic configuration. E.g.
IE Be > IE B
IE N > IE O
How do Atomic radius vary in group and period?
Group - Increases
Period - Decreases
Define 2nd IE.
The minimum amount of energy required to remove an electron from an isolated gaseous mono positive cation is 2nd IE.
Compare the ionization energy of :
a) Li and Na b) N and O c) K and Ca
Li > Na ( Increased no of shells)
N > O (Half filled p subshell in N)
Ca > K ( Across the period and full filled s subshell)
Why is 2nd IE greater than 1st IE?
- After the first electron is removed, the remaining electrons experience a stronger attraction to the nucleus.
- Decrease in Shielding effect due to reduced number of electrons
Some exceptions in electronic configuration of elements from 21 - 30 :
Some exceptions like chromium and copper due to electron configurations being adjusted for stability (half-filled and fully-filled d-orbitals).
What is electropositivity?
The tendency of an atom to lose an electron / electrons to form cation is called electropositivity.
Relation between IE and electropositivity :
High IE = Less electropositivity
Low IE = High electropositivity
Difference between IE and electropositivity :
Electropositivity is a qualitative property describing the ease of losing electrons, while ionization energy is a quantitative measure of the energy required to do so.
